but if I get into any trouble to rely on the fact that I can't speak any Japanese (she also said that this is what she and her Japanese friends do when something goes wrong while they are in the US )

You can do that to the police, but not to the local residents. Or you'll be cooked in a pan.

Generally speaking, the Shikoku people don't really like outsiders of any kind. I felt that strongly in some parts of Shikoku when I did another trip there. In Kochi, someone put a nail and busted the wheel on my car overnight. It wasn't hard to guess because my car was the only one with an out-of-prefecture/state license plate in the parking lot. Also I wasn't very welcomed in a cafe when I went in there to get breakfast near there. I had a few bad real ugly moments, and that's not uncommon.

But at the same time, I had fun, too. In a fishing village called Hiwasa in Tokushima, in a small eatery, I was invited to the table shared by the local fishermen and the farmers. They poured a lot of "Shochu", Japanese gin into my glass out their daily kept bottles, and we talked and talked. We talked a lot of things. They liked me as an unusual guest, and later, they introduced me to another friend of theirs, also a fisherman. He took me on a boat ride at mid-night to go catch "Iseebi", Japanese lobster. It's was real fun, but I don't think they do so often to the tourists.